Effect of ranolazine on atrial fibrillation in patients with non-ST elevation acute coronary syndromes: observations from the MERLIN-TIMI 36 trial.

AIMS: To determine the effect of ranolazine, an anti-ischaemic agent with anti-arrhythmic properties, on the overall burden of atrial fibrillation (AF) in acute coronary syndromes (ACS) and determine whether ranolazine reduces the long-term incidence of clinical AF after ACS. METHODS AND RESULTS: MERLIN-TIMI 36 randomized patients with non-ST elevation ACS to ranolazine or placebo. Atrial fibrillation episodes detected on continuous electrocardiogram (cECG) monitoring were reviewed in 6351 patients (97% of trial). Atrial fibrillation burden was categorized according to the time in AF: clinically insignificant AF (<0.01% of time), paroxysmal AF (>0.01-98%), or predominantly persistent AF (>98%). Clinical AF events were identified through adverse event reporting for a median 1-year follow-up. Overall, patients assigned to ranolazine had a trend towards fewer episodes of AF [75 (2.4%) vs. 55 (1.7%) patients, P = 0.08] detected on cECG during the first 7 days after randomization. The pattern of new-onset AF differed between ranolazine vs. placebo: clinically insignificant AF (five patients in ranolazine vs. seven in placebo), paroxysmal AF (18 vs. 48 patients), and predominantly chronic AF (28 vs. 20 patients, three-way P < 0.01). Among patients with a paroxysmal AF pattern, the overall burden was lower with ranolazine than with placebo (median 4.4 vs.16.1%, P = 0.015). Over the median 1-year follow-up, fewer patients treated with ranolazine experienced an AF event compared with placebo (2.9 vs. 4.1%, RR 0.71, P = 0.01). CONCLUSION: Ranolazine, an anti-anginal agent with electrophysiological effects, may reduce the frequency of paroxysmal AF in patients with non-ST elevation ACS with a pattern of lower overall AF burden in this group. Ranolazine reduced the overall 1-year incidence of clinical AF events. These atrial-specific anti-arrhythmic properties of ranolazine may be of clinical interest and warrant additional investigation. CLINICAL TRIAL REGISTRATION: NCT00099788.

The risk of sudden cardiac death in patients with non-ST elevation acute coronary syndrome and prolonged QTc interval: effect of ranolazine.

AIMS: Clinical utility of QTc prolongation as a predictor for sudden cardiac death (SCD) has not been definitely established. Ranolazine causes modest QTc prolongation, yet it shows antiarrhythmic properties. We aimed to determine the association between prolonged QTc and risk of SCD, and the effect of ranolazine on this relationship. METHODS AND RESULTS: The relationship between baseline QTc and SCD was studied in 6492 patients with non-ST elevation acute coronary syndrome (NSTEACS) randomized to placebo or ranolazine in the MERLIN-TIMI 36 trial. In the placebo group, an abnormal QTc interval (≥450 ms in men, ≥470 ms in women) was associated with a two-fold increased risk of SCD (hazard ratio, HR, 2.3, P = 0.005) after adjustment for other risk factors (age ≥75 years, NYHA class III/IV, high TIMI risk score, ventricular tachycardia ≥8 beats, digitalis, and antiarrhythmics). In the ranolazine group, the association between abnormal QTc and SCD was similar to placebo, but not significant (HR 1.8, P = 0.074). There was no significant difference between placebo and ranolazine in the risk for SCD in patients with abnormal QTc (HR 0.78, P = 0.48). When QTc was used as a continuous variable, for every 10 ms increase in QTc, hazard rate for SCD increased significantly by 8% (P = 0.007) in the placebo group, and only by 2.9% (P = 0.412; P for interaction=0.25) in the ranolazine group. CONCLUSION: In NSTEACS patients treated with placebo, prolonged QTc was a significant independent predictor for SCD. Ranolazine, compared with placebo, was not associated with increased risk for SCD in patients with prolonged QTc.

Effects of ranolazine on exercise tolerance and angina frequency in patients with severe chronic angina receiving maximally-tolerated background therapy: analysis from the Combination Assessment of Ranolazine In Stable Angina (CARISA) randomized trial.

BACKGROUND: Ranolazine has been previously shown to improve exercise capacity and symptoms in patients with severe chronic angina treated with standard doses of beta-blockers and calcium-channel blockers, without a significant effect on heart rate or blood pressure. OBJECTIVE: The purpose of this study was to assess whether the benefit of ranolazine extends to the subgroup of angina patients treated with maximally-tolerated doses of beta-blockers or calcium blockers. METHODS AND RESULTS: In this post-hoc analysis, 258 patients from the Combination Assessment of Ranolazine In Stable Angina (CARISA) trial were considered as treated with maximally-tolerated doses of beta-blockers or calcium-channel blockers (systolic blood pressure (SBP) ≤ 100 mm Hg, and/or a resting heart rate ≤ 60 beats per minute, and/or an ECG PR interval ≥ 200 msec). Change from baseline in total exercise duration after 12 weeks compared to placebo were 34.5 (95% CI 0.8; 68.1) sec (p = 0.045) with ranolazine (750/1000 mg bid) at trough drug levels and 46.3 (13.5; 79.1) (p = 0.006) at peak drug levels. The number of angina attacks per week compared to baseline were reduced compared to placebo (-2.3 ± 0.3 vs -0.9 ± 0.6 (p < 0.001)). The effects of ranolazine 750 mg bid and 1000 mg bid were similar and the beneficial effects of ranolazine in this subgroup of maximally-treated patients were consistent with those not on maximally-tolerated doses of the background therapy. CONCLUSION: Ranolazine is effective for the symptomatic treatment of patients with stable angina on background therapy with maximally-tolerated doses of first line anti-anginal therapies.

In-hospital mortality in patients with acute decompensated heart failure requiring intravenous vasoactive medications: an analysis from the Acute Decompensated Heart Failure National Registry (ADHERE).

OBJECTIVES: We sought to compare the in-hospital mortality of patients with acute decompensated heart failure (ADHF) who were receiving parenteral treatment with one of four intravenous vasoactive medications. BACKGROUND: There are limited data regarding the effects of the choice of intravenous vasoactive medication on in-hospital mortality in patients hospitalized with ADHF. METHODS: This was a retrospective analysis of observational patient data from the Acute Decompensated Heart Failure National Registry (ADHERE), a multicenter registry designed to prospectively collect data on each episode of hospitalization for ADHF and its clinical outcomes. Data from the first 65,180 patient episodes (October 2001 to July 2003) were included in this analysis. Cases in which patients received nitroglycerin, nesiritide, milrinone, or dobutamine were identified and reviewed (n = 15,230). Risk factor and propensity score-adjusted odds ratios (ORs) for in-hospital mortality were calculated. RESULTS: Patients who received intravenous nitroglycerin or nesiritide had lower in-hospital mortality than those treated with dobutamine or milrinone. The risk factor and propensity score-adjusted ORs for nitroglycerin were 0.69 (95% confidence interval [CI] 0.53 to 0.89, p < or = 0.005) and 0.46 (94% CI 0.37 to 0.57, p < or = 0.005) compared with milrinone and dobutamine, respectively. The corresponding values for nesiritide compared with milrinone and dobutamine were 0.59 (95% CI 0.48 to 0.73, p < or = 0.005) and 0.47 (95% CI 0.39 to 0.56, p < or = 0.005), respectively. The adjusted OR for nesiritide compared with nitroglycerin was 0.94 (95% CI 0.77 to 1.16, p = 0.58). CONCLUSIONS: Therapy with either a natriuretic peptide or vasodilator was associated with significantly lower in-hospital mortality than positive inotropic therapy in patients hospitalized with ADHF. The risk of in-hospital mortality was similar for nesiritide and nitroglycerin.

Clinical and hemodynamic effects of nesiritide (B-type natriuretic peptide) in patients with decompensated heart failure receiving beta blockers.

The use of beta blockers in congestive heart failure presents a therapeutic challenge for patients with acute episodes of decompensation. Such patients may be less responsive to positive inotropic agents, whereas the beneficial effects of nesiritide, which are not dependent on the beta-adrenergic receptor signal-transduction pathway, may be preserved. This analysis of the Vasodilation in the Management of Acute CHF trial evaluated the safety and efficacy of nesiritide in decompensated congestive heart failure patients receiving beta blockers. The Vasodilation in the Management of Acute CHF trial was a multicenter, randomized, controlled evaluation of nesiritide in 489 hospitalized patients with decompensated congestive heart failure. One hundred twenty-three patients were on chronic beta-blocker therapy at enrollment (31 randomized to placebo, 50 to nesiritide, and 42 to nitroglycerin). Primary end points included pulmonary capillary wedge pressure and dyspnea evaluation at 3 hours. Patients receiving nesiritide, but not IV nitroglycerin, had significantly reduced pulmonary capillary wedge pressure vs. placebo at 3 hours regardless of beta-blocker use. The use of beta blockers did not alter the beneficial effects of nesiritide on systemic blood pressure, heart rate, or dyspnea evaluation. In nesiritide-treated subjects, safety profiles were similar regardless of beta-blocker use. Thus, the clinical and hemodynamic benefits and safety of nesiritide are preserved in decompensated congestive heart failure patients receiving chronic beta blockade.

Effect of nesiritide (B-type natriuretic peptide) and dobutamine on ventricular arrhythmias in the treatment of patients with acutely decompensated congestive heart failure: the PRECEDENT study.

BACKGROUND: Dobutamine is commonly used as a means of treating decompensated congestive heart failure (CHF). Although typically effective at improving short-term hemodynamics and symptomatology, the frequent occurrence of arrhythmias and tachycardia is undesirable. In this randomized, multicenter trial, we compared the safety and clinical effectiveness of the cardiac hormone nesiritide (human B-type natriuretic peptide) with dobutamine in hospitalized patients with decompensated CHF. METHODS: The study population consisted of 255 patients who were randomized to 1 of 2 doses of intravenous nesiritide (0.015 or 0.03 microg/kg/min) or dobutamine (> or =5 microg/kg/min) and stratified by means of an earlier history of ventricular tachycardia. Patients were also assessed with 24 hour Holter recordings immediately before and during study drug therapy and by means of signs and symptoms of CHF. RESULTS: Dobutamine significantly increased the mean (1) number of ventricular tachycardia events per 24 hours by 48 +/- 205 (P =.001), (2) repetitive ventricular beats per hour by 15 +/- 53 (P =.001), (3) premature ventricular beats per hour by 69 +/- 214 (P =.006), and (4) heart rate by 5.1 +/- 7.7 beats per minute (P <.001). These end points were significantly decreased or unchanged in the nesiritide groups. Nesiritide did not increase heart rate, despite a greater reduction of blood pressure. Both drugs were similarly effective means of improving signs and symptoms of CHF. CONCLUSIONS: Dobutamine is associated with substantial proarrhythmic and chronotropic effects in patients with decompensated CHF, whereas nesiritide actually reduces ventricular ectopy or has a neutral effect. Compared with dobutamine, nesiritide may be a safer, short-term treatment for patients with decompensated CHF.